7-Way and 4-Way Trailer Connector for a 2000 GMC Sierra with 3 Wire System

Question:

I was wanting to know if I could use this to pull either a 7 or 4 way pluged trailer? I have a 7 way on my truck, but when I try to use just the 7 to 4 way adapter I dont have brake lights. I was told to get a power convertor, but this limites me to just 4 way plugs. So, would this product allow me to use either a 7 or 4 with no convertor? Thanks for the help!

asked by: Jerimiah W

Expert Reply:

You should not need a converter for your GMC Sierra pickup. I would recommend using a circuit tester like # PTW2993 and testing the pins on the existing connector. By clicking on the wiring FAQ link I provided, you can see what pin serves which function. You should also check the fuses that protect your trailer wiring circuits, which are located in the fuse box under the hood. The lid of the fuse box should have a legend on it that will tell you which fuses serve which purpose.

If your 2000 GMC pickup has the round connector located underneath the vehicle close to the rear bumper or above the spare tire, then you will be able to use the OEM Style 7-Way and 4-Way Trailer Connectors for Ford and GM Trucks, item # HM40975, to replace your 7-Way only connector and have a 7-Way and 4-Way connector available for towing. If the factory wiring harness terminates in bare wires, and has no connector, you would also need the pigtail, # PK11998.

expert reply by: Robert G